In a semiconductor integrated device including multiple stacked semiconductor chips, namely, in a so-called MCP (Multi Chip Package), one pad or signal wiring is shared by the multiple semiconductor chips. Accordingly, a large load is placed on the signal wiring, and the transmission speed of the signal decreases. Therefore, there is a problem in that a sufficient transmission speed cannot be obtained.
In contrast, there is a semiconductor device in which the semiconductor element is divided into multiple blocks, and a clock signal is supplied to only an intended block. Such kind of semiconductor device is disclosed in Japanese Patent Application Publication No. 2-2991.
The above semiconductor device is a clock synchronization-type semiconductor integrated device including multiple storage elements which are brought into synchronization by using at least one clock signal or inverted clock signal generated by a clock signal generation unit and supplied via multiple clock drivers. The storage elements are divided into minor blocks in such a manner that storage elements located in proximity to each other in terms of the physical layout are grouped into the same minor block or in such a manner that storage elements having a high degree of logical coupling with each other are grouped into the same minor block. A buffer circuit is arranged in each of the minor blocks. In the previous stage of the buffer circuit, a transmission gate is arranged to control whether the clock signal is supplied or not.
Accordingly, the clock signal is supplied only to the intended block, and the other blocks are electrically separated. Therefore, the redundant load placed on the clock signal line can be reduced, and the delay of the clock signal can be reduced.
However, in the semiconductor device, each block is connected to the clock signal line in parallel. Accordingly, as the number of intended blocks increases, the delay of the clock signal increases. As a result, there is a problem in that a sufficient transmission speed cannot be obtained.